The present invention relates generally to devices for accurately transferring multiple, individual fluids from multiple source containers into a single receiving container. More specifically, the present invention relates to a transfer set for use in such devices.
U.S. Pat. No. 4,789,014 discloses an automated system for adding multiple fluids to a single container. The device as described accurately transfers multiple individual fluids from multiple source containers into a single receiving container. Fluid flows from the multiple source containers through individual fluid conduits to a chamber having a single fluid outlet conduit. The fluid outlet conduit is in fluid communication with a single receiving container. A pressure conduit is in communication with the chamber for alternately creating positive and negative pressures in the chamber to cause fluid to flow from the individual source containers into the chamber, and to cause fluid to flow from the chamber into the receiving container in response to commands from a controller.
In hospitals, it is frequently necessary to provide solutions for intravenous administration to a patient which contain a variety of drugs in a single solution container. For example, such a need arises when a patient is receiving all of his nutritional needs intravenously. In this situation, the patient will typically receive a basic solution containing amino acids, dextrose, and fat emulsions which provide a major portion of the patient's nutritional needs. However, this solution is insufficient to maintain a patient for an extended period of time.
Therefore, a typical total parenteral nutrition solution includes as many as eight to twelve additional additives. The additives are typically minute quantities of vitamins, minerals, electrolytes, etc.
One way to prepare the necessary solutions for total parenteral nutrition is for the pharmacist to individually add each of the additional additives to a solution container after the base solution has been prepared. This is typically done with individual syringes and requires a relatively long time on the part of the pharmacist to accurately add each of the required additives.
Automated compounding devices have been developed to assist the pharmacist in preparing solutions for total parenteral nutrition. An example of such a device is described in U.S. Pat. Nos. 4,467,844 and 4,513,796. This device is used to assist the pharmacist in automatically compounding base solutions of amino acids, dextrose, and fat emulsion. The system typically uses three or more peristaltic pumps to individually pump each of the base solutions from three or more separate source containers. Computer software has been developed and is used to program the amount of solution required for a series of individual patients.
Examples of automated compounding machines include the Automix.RTM. and Micromix.RTM. compounders distributed by Clintec Nutrition Company.
With respect to the Micromix.RTM. compounder, disclosed in U.S. Pat. No. 4,789,014, the device includes a transfer set. The transfer set is used to transfer fluids from each of the individual containers to a receiving container. The transfer set includes a tray in which the fluid conduits are located. The fluid conduits are designed to be connected to specific containers containing specific fluids.
Although the current transfer set functions satisfactorily in the Micromix.RTM. compounder, to insure that there is no operator or manufacturing error, rigorous QC and other testing is performed. For example, in a typical Micromix.RTM. compounder transfer set, ten separate fluid conduits are positioned in the tray. Although these fluid conduits, when manufactured and packaged, are typically arranged so that they can be easily coupled to the specific containers and positioned in the Micromix.RTM. compounder, if a manufacturing problem were to occur and a fluid flow path is crossed, this could result in a fluid conduit being coupled to the wrong container, and an incorrect solution being created if not discovered by the operator. Therefore, extensive testing is performed at the factory to insure any such mistakes are caught at the factory.
Additionally, the transfer set is designed to be located so as to allow a first occlusion means to selectively prevent fluid flow from each of the individual fluid conduits to a chamber. If the transfer set is not properly located in the first occlusion means, the system will not function. To locate the transfer set in proper position with respect to the first occluder, holes are located at an end of the tray. The holes are then aligned in the occluder to insure that the transfer set is properly positioned therein.
In the current transfer set used in the Micromix.RTM. compounder, the holes are created in the transfer set in a secondary stamping or punching operation. Alignment problems can occur if the holes created during secondary operation are not properly located and are out of machine tolerances; this will prevent the occluder from working.
Heretofore, typically the transfer sets, when created, are sealed around the fluid conduits during the manufacturing process. After the manufacturing process, the fluid conduits are checked for leaks or other problems. If a problem is discovered in an individual fluid conduit, because the transfer set is sealed, it is not possible to remedy the problem. Instead, the transfer set and enclosed fluid conduits must be scrapped. This results in a not insubstantial loss.